Figure 1.
FIGURE 1. Ribbon representation of human GalNAc kinase.
Human GalNAc kinase folds into two motifs referred to as the N-
and C-terminal domains. As indicated in a, the N-terminal domain
is dominated by a seven-stranded mixed -sheet highlighted in
magenta. Two layers of antiparallel -sheet, colored in
yellow and blue, characterize the C-terminal domain. The
location of the active site is indicated by the ball-and-stick
representations for GalNAc-1-phosphate and MgADP, with the Mg2+
ion highlighted in green. Electron density corresponding to
GalNAc 1-phosphate and MgADP is displayed in b. While the
protein was crystallized in the presence of GalNAc and MgATP,
the electron density clearly reveals that the enzyme is active
in the crystalline lattice. The map, contoured at 2 , was
calculated with coefficients of the form F[o] - F[c], where F[o]
was the native structure factor amplitude, and F[c] was the
calculated structure factor amplitude from the model lacking
coordinates for the ligands. A close-up view of the active site
with bound products is depicted in c. Only those residues
located within 3.2 Å of the
ligands are shown. The green dashed lines indicate coordinate
covalent bonds between the magnesium ion and its ligands. The
black dashed lines indicate potential hydrogen bonding
interactions. For clarity, Ser141 and Gly143 were omitted from
the figure.
The above figure is reprinted
by permission from the ASBMB:
J Biol Chem
(2005,
280,
32784-32791)
copyright 2005.
-sheet highlighted in
magenta. Two layers of antiparallel 
, was
calculated with coefficients of the form F[o] - F[c], where F[o]
was the native structure factor amplitude, and F[c] was the
calculated structure factor amplitude from the model lacking
coordinates for the ligands. A close-up view of the active site
with bound products is depicted in c. Only those residues
located within 
3.2 Å of the
ligands are shown. The green dashed lines indicate coordinate
covalent bonds between the magnesium ion and its ligands. The
black dashed lines indicate potential hydrogen bonding
interactions. For clarity, Ser141 and Gly143 were omitted from
the figure.